In this brief, the silicon nanowire transistor (SNWT)-based circuits of current mirrors (NWCMs) have been successfully fabricated for the first time. The key figures of merit of current mirrors (CMs) are experimentally studied, including output voltage coefficient (OVC), output resistance, and dc matching error ε. The experimental results indicate that, due to the unique quasi-1-D transport properties of the SNWTs, NWCMs exhibit superior performance than planar metal-oxide-semiconductor-field-effect-transistor-based CMs (PCMs) in the inversion operation region. Furthermore, NWCMs operating in the subthreshold region shows even better performance than PCMs. With the inherent advantages of the gate-all-around structure, the SNWT is very promising for analog and mixed-signal integrated circuits and particularly has its unique potential at subthreshold operation for low-power applications.